Evidence of size-dependent Effect of Silica micro- and nano-particles on Basal and Specialized Monocyte Functions

Abstract

Aim: To analyze the effect of silica particles on monocyte/macrophage functions. Materials & methods: Silica micro- and nanoparticles were obtained by the Stöber method. Their effect on monocyte/macrophage proliferation, activation, membrane integrity and metabolic activity were determined. Results: Silica particles inhibit cell proliferation while 10 nm nanoparticles (NPs) did not affect it. Similarly, silica particles induced strong cell activation. However, 10 nm NPs do not alter IL-12 or nitrite levels. Furthermore, bigger NPs and microparticles increase cell membrane damage and reduce the number of living cells but smallest NPs (10 and 240 nm) did not. Conclusion: Cell activation properties of silica particles could be useful tools for immune stimulation therapy, while 10 nm NPs would be suitable for molecule transportation.

Keywords:

• activation markers
• cell activation
• cytokine secretion
• monocytes/macrophages
• silica nanoparticles

Conflicts of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Financial & competing interests disclosure

R Mitarotonda is grateful for her doctoral fellowship granted by Universidad Nacional de Luján. This work was supported by the under grant from the Universidad de Buenos Aires UBACYT 20020150100056BA, under grant from CONICET PIP 11220120100657CO, under grant from Agencia Nacional de Investigaciones Cientificas y Técnicas PICT 2012–1441 and PICT 2015–2922 (to MF Desimone), under grant from UNLu-CDD-CB number 402–11 and under grant from CONICET-PIP 11420110100375 (to MC De Marzi). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.